Field of the Invention
The present invention relates to a valve apparatus having a valve plug movable in an axial direction, and which is configured to interrupt a communication state of a flow channel as a passage of fluid when the valve plug is seated on a valve seat surface of a body.
Description of the Related Art
Heretofore, valve apparatuses capable of switching a flow state of fluid flowing thorough a flow channel has been known. For example, in Japanese Laid-Open Patent Publication No. 2013-050145, a valve plug is provided inside a body so as to be movable in an axial direction, and the valve plug is coupled to a piston rod, while the valve plug can be seated on a valve seat provided inside the body. The valve seat is formed in a ring shape. A plurality of recesses are formed in a valve seat surface of the valve seat facing the valve plug. The recesses extend in a radial direction, and are arranged side by side in a circumferential direction.
When the valve plug is seated on the valve seat surface of the valve seat, flow of fluid through the inside of the body is interrupted. In a valve opening operation where the valve plug moves away from the valve seat, since the contact area between the valve seat and the valve plug is smaller owing to the presence of the plurality of recesses, sticking between the valve seat and the valve plug is prevented.